rcutorture: Make rcutorture_one_extend_check() account for hard IRQs

rcutorture: Make rcutorture_one_extend_check() account for hard IRQs

This commit retrospectively prepares for testing of RCU readers invoked
from hardware interrupt handlers (for example, HRTIMER_MODE_HARD hrtimer
handlers) in kernels built with CONFIG_RCU_TORTURE_TEST_CHK_RDR_STATE=y,
which is rarely used but sometimes extremely useful.  This preparation
involves taking early exits if in_hardirq(), and, while we are in the
area, a very early exit if in_nmi().

This means that a number of insoftirq parameters are no longer needed,
but that is the subject of a later commit.

Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202505140917.8ee62cc6-lkp@intel.com
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.upadhyay@kernel.org>